Wall-type chain mortising machine



Sept. 24, 1957 G. STOLL ETAL 2,807,296 I WALL-TYPE CHAIN MORTISINGMACHINE Piled'April 22, 1953 2 Shets-Sheet 1 FIG. 10

INVENTORS 6015132591, \StoZZ v y Geo r9 Jab-e Sept. 24,-1957 G. STOLLEIAL 2,807,296 WALL-TYPE CHAIN MORTISING MACHINE Filed April 22, 1953 2Sheets-Sheet 2 JNV TOR: Got! Zia 670? y Gabi-9 \S'cZ. ray

Unitd States I Patent Ofiiice 2,807,296, 7 Patented Sept. 24, 1957 mamasWALL-TYPE CHAIN MORTISING MACHINE Gottlieb Stoll and Georg Schrag,Esslingen Neckar,

- Germany It is well known that chain mortising machines which are to befixed to a wall or a column, so-called wall-type chain mortisingmachines, exist in various designs. There are designs in which the lowerpart is equipped with a clamping table to be fixed to the wall or acolumn, while the upper part containing the motor which can be raisedand lowered by means of a hand-lever, may be shifted longitudinally andtransversely on the lower part and inclined laterally and rotated on avertical axle. Such a machine can be used in many ways, but it is anunwieldy device, and therefore expensive. Another disadvantage is thatit has a great overhang as against the fastening surface and requires,in consequence, extremely rigid fixing. Another well-known design has aguiding frame for the motor driving the mortising chain and is arrangedfor longitudinal and transverse adjustment on an upper machine partwhich is to be fixed to the wall. On the lower end of this upper partthe clamping table can be inclined in a vertical plane, and may, in caseof need, be turned on a vertical axle. Other designs are known in whichthe driving motor of the chain mortising tool is guided in the upperpart of the machine fixed to a wall or column, only for raising andlowering. In this case the upper part of the machine is provided at itslower end with a cross-slide together with a longitudinal slide fortaking up the workpiece which longitudinal slide can be adjusted tovarious inclinations for mortising cotter-slots. This design enables alighter construction which affords more favourable fixing facilities onaccount of the reduced overhang from the fastening surface. However, itcannot be used in as many ways as the first-mentioned type.

The object of the invention is an improvement of the last-mentioned typeof wall chain mortising machines to the eifect that the cross-slidepiloting the longitudinal slide is guided by an element fitted to thelower side of the upper part of the machine and adjustable on a verticalaxle. Thus, the clamping table may not only be shifted longitudinallyand transversely and swivelled to various inclinations, but it may alsobe swivelled horizontally. That is to say it is possible to give theworkpiece any desired position with respect to the mortising chain-tool.The universal applicability of the machine resulting therefrom isachieved by a simple and easy construction. Y

A particularly favourable construction of the machine is obtained byadopting the following arrangements: The cross-slide is mounted in therotary-adjustable support on the upper part of the machine by means of ajournal screwed on to the setting spindle, so that it can swivel in alimited angle on the axle of the journal. Moreover, it can be fixed invarious inclinations by means of a stop engaging with a tooth segment ofthe rotaryadjustable support, the teeth of the segment being arrangedparallel to the sliding direction of the cross-slide, so that they keepin mesh with the stop when the crossslide is moved.

Apart from expensive rack-and-pinion gears operated by a handwheel,pivoted lever arrangements are also known for moving the longitudinalslide. In such arrangements the operating lever can be swivelled in avertical plane behind the clamping surface of the longitudinal slide.According to the invention arswivelling lever for moving thelongitudinal slide on a vertical axle, that is to say in a horizontalplane, is fitted pivoting on the cross-slide and with a bent arm, to aconnecting-rod on the back of the longitudinal slide. The hand-leverprotruding horizontally beyond the longitudinal slide is much easier tooperate than a lever swinging in a vertical plane behind the clampingsurface of the longitudinal slide. A further new feature of theinvention is that the swivelling range of the hand lever is equal to afraction only of the entire sliding-way of the longitudinal slide,whereby the connecting-rod for the longitudinal slide is provided withvarious working points for the hand-lever in order to obtain variousshifting-ranges. Whereas in the designs known hitherto the swivellingrange of the hand-lever is in correspondence with the total path of theslide, in the present invention the power required for moving the slideis considerably reduced which facilitates work, especially where it is acase of long and heavy workpieces, and renders possible precise andcareful adjustment of the slide. Another feature of the invention isthat the lever can be shifted to another range easier and quicker byconnecting several mortise borings of the connecting-rod by alongitudinal slot for a connecting pin of the hand-lever, and making thehandlever movable upwardly to a limited extent only Whereby itsconnecting pin is moved out of the mortise boring of the connecting-rod,and a lighter guide-bolt fitting into the connecting slot is ready topass into another mortise hole.

The longitudinal slide is guided along the cross-slide preferably bymeans of a pair of round bars on the longitudinal slide placed one ontop of the other and inserted between its front walls. The round barguidance is simple and of great precision. It permits, in addition, ofcorrecting the position of the clamping slide in correspondence with themortising chain path in order to obtain equality in the thickness ofchecks of the workpiece on both sides of the finished mortise. For thispurpose, for instance, the longitudinal slide may be adjustedtransversely in moderate degrees as against the lower round bar byswinging it on the upper round bar. In a preferential embodiment of theinvention the lower round bar is conducted through the front walls ofthe longitudinal slide with a clearance for lateral movement, and restson straps on the outside of the front walls which straps are fixedtransversely adjustable on the front walls. Apart from that set screwsadjustable to the lower round bar may be provided in the front walls ofthe longitudinal slide for adjusting the oblique position of the slide.Re-

adjustment of the slide may also be realized by mounting the lower roundbar passing through the front Walls of the longitudinal slide with aclearance for lateral movement, on the straps arranged for swivelling onthe out side of the front walls, by means of eccentrically arrangedend-journals, and making it rotatable by a hand-lever fixed on one ofthe eccentric journals.

Other characteristic features of the invention are described togetherwith the embodiments of the invention illustrated in the accompanyingdrawings, in which:

Figure 1 is a front elevation of the machine, Figure 2 is asideelevation of the machine, Figure 3 is a section taken on line III'III ofFig. 1, Figure 4 is a its sliding drive,

Figure 5 is a section taken on lineV-'V'of Fig.4; Figure 6 is'a frontview of the longitudinal slide with theadjustmentdevice,

plan view of the longitudinal slide with Figure 7 is a section taken online VII-VII of Fig. 6,

Figure 8 is a front view of the longitudinal slide of another embodimentof the adjustment device,

Figure 9 is a section taken on line IXIX of Fig. 8,

Figure is a cross section of a detail taken on line XX of Fig. 1,

Figure 11 is a cross section of a detail taken on line XL-XI of Fig. l,and

Figure 12 is a cross section of a detail taken on line XII-XII of Fig.3.

The upper part of the machine has a box-like stand 1 which at its fourcorners is provided with eye-lugs for fixing it to a wall or column. Infront of the partly-open front of the box-like frame or stand 1 twovertical guide columns 4 are inserted between eye-lugs 3 protrudingahead on which columns 4 the mortising chain driving motor 5 withlateral guiding eyes 6 is mounted for raising and lowering. Motor 5drives in well-known manner the mortising chain 7 by means of achain-wheel mounted on its shaft, which mortising chain 7 is conductedaround a guiding-bar 8 fixed on the front of the motor and. directeddownwards. The motor 5 is suspended together with a pedestal 9 in alever-arm 11 by the use of intermediate levers 10, the lever-arm 11swivelling on an axle 12 rigidly arranged in frame 1. The lever-arm 11is the longer arm of a double lever, the shorter arm of which isconnected with a tension spring 14 arranged along and near the back wallof the box-like frame 1 and fixed at its bottom end. The attachment maybe made adjustable for changing the tension of the spring. Preferablytwo springs 14 are provided, running parallel to each other and attachedto twofork ends of lever 13. By springs 14 the motor is kept in thehighest position as illustrated in Figs. 1 and 2 in which the mortisingchain 7 may be moved against a workpiece.

In the embodiment of the invention illustrated by Figs. 1 and 2 themotor is raised and lowered by a hand-lever. Hand lever 15 is connectedwith a head piece 16 mounted on an upper face of the transmission lever11. Lever 15 or, respectively, headpiece 16 is not, however, rigidlyconnected with lever arm 11, but in such manner only as to give it apossibility of swinging out laterally to a limited extent. In the aboveembodiment of the invention such possibility of swinging out laterallyis provided in that the head piece 16 can swing on a front fixing. screw17 and that it has a moving clearance against a back fixing screw 18.The rear end of head piece 16 is formed into a locking pawl 19 which, assoon as the highest position of the hand lever 15 is reached and thehand lever. 15 swings out laterally, notches in the back of a catchingpin 20 projecting from behind the upper part of frame 1. Therefore, whena working stroke is to be executed, the hand lever 15 must first beswung out a little laterally, so as to disengage pawl 19 from the catchpin 20, and thereby release the hand-lever for turning t it down. Inthis manner security is obtained against unintentional switching-on ofthe machine.

On a side-wall of frame 1 (Fig. l on the left) the motor-switch 21 isfixed. One of the fork ends of the switch lever 22 of the motor switchextends to the operation range of a stop 23 arranged on a lateral lug 24of the motor guiding eye 6 on the switch side. The arrangement is suchthat as soon as the motor has arrived at the highest position, theswitch is off,'and it is on when the cage is going down so that themortising chain rotates. When returning the motor to its uppermostposition, switch 21 is off again. The lead wire 25 between the motor andswitch is conducted along a cut-out'26 in the side-wall of frame 1.Moreover, a rod 27 is arranged parallel to the guide column'4 on whichrod movable end-collars 28 and 29 are arranged which may be fixed byset-screws 30. As an accessory to these end-collars there is a stop pin31 arranged for shifting'inan'd out on lug 24 of the motor below thecontrol pin 23 of the motor switch. In Fig. 2 stop pin 31 is shownshifted out, in which position the stop pin as well as the control pincan pass the upper stop ring 29, and will hit the lower stop-ring 28only which is then the lower stroke limit. In this case, therefore, themotor is moved back to the highest position while the switch 21 is againplaced to off-position. When the stop pin 31 is moved inside afterlowering of the motor, the upper stop ring 29 constitutes an upperstroke limiting stop, and the motor can be raised or lowered within thepositions limited by rings 28 and 29. Stop 23 remaining below switchlever 22 of motor switch 21, the motor is not switched off during theupstroke, i. e. the mortising chain 7 keeps running continuously as longas the operation is carried on with this limiting of the stroke.

A guide element. 33 is fixed to the lower side of the box like frame 1by means of a flange 34. Flange 34 is centered in a boring at the bottomof the box by means of a journal 35. The guide element 33 is attached tothe bottom of the box by means of a fixing screw 37 screwed from aboveinto journal 35 through a covering disc 36 overlapping the boring of thebox. By loosening screws 37 and 38, the firm initial tension of flange34 with the bottom of the box is relaxed, and element 33 may be turnedon the axis of its journal 35. The extent of the turningmay be read offfor instance from a graduated scale of flange 34 by means of astationary indicator fixed at the bottom of the box. Element 33 is,therefore, fixed for adjustable turning on the lower end of the upper machine part. Moreover, flange 34 is screwed on fast to the bottom of thebox from below by for instance two screws 38 passing through arc-likeslots of the flange.

Element 33 serves for guiding a cross-slide 40. This cross-slide 40 is(see particularly Fig. 3) inserted in a cross boring of guiding element33 by means of a guide pin. and is screwed on to a threaded spindle 42which is connected with a turnable handwheel 43 on the op posite end ofthe guiding element 33, but fixed in the direction of the axis. In orderto prevent cross-slide 40 from swinging on the axi of its guide-pin 41,a holding pin 45 is made to clutch with a tooth arrangement 46 in an arm44 overhanging the sliding body laterally and backwards, which tootharrangement is arranged on arm 48 of the rotatably-adjustable guidingelement 33. The holding pin 45 the end of which is adapted to fit intothe tooth-spaces of tooth arrangement 46, is movable in arm 44, andsecured against being over-turned. It is of advantage to provide aspring-not illustrated-which presses the holding pin 45 automaticallyinto the tooth arrangement 46. For operation the holding pin 45 has ahandle 49. By introducing the holding pin into various tooth spaces thecross-slide 40 may be adjusted to'various inclinations. The tootharrangement 46 is made parallel to the shifting direction of thecross-slide so that when shifting the cross-slide, the meshing of theholding-pin 45 is maintained. The cross-slide is shifted by turning thehandwhecl 43whereby the threaded spindle 42 turning with it eitherpushes the stationary guide pin 41 of cross-slide 40 outside, or drawsit inside. The swinging movement of cross-slide 49 is limited downwardby tooth 50 of [toothsegment 46 which tooth 50 protrudes in radialdirection over the other teeth of the tooth segment 46 as far as toforman abutment for the holding pin45 in its disengaged tposition.

Cross'slid'e" 40 is the guide for longitudinal slide 52. Two round bars53 are used for guiding same. These bars 53 are inserted between frontwalls 54 leading backwards, of the longitudinal slide 52, and aremovable in borings. of the cross-slide arranged vertically one above theother. A- hand' lever 55 is provided for moving the longitudinal slide52,,along the cross-slide, which hand lever 55 is positioned to rotatein a vertical upright socket 57 of the cross slide. The hand leverextends above over the cross-slide toward the front, and is connected,by means of lever-arm 58, to a connectingarod 59 which is swingabl'y'connected in a horizontal plane to an eye 60 projecting from the back ofthe longitudinal slide 52. The shifting movement of the longitudinalslide can be limited on both sides by rod members 51 fitted foradjusting and fixing in the front wlalls of longitudinal slide 52, andoperating by abutting against the side surfaces of cross-slide 40, Fig.3. The length of the short lever-arm 58 is such that with a swivellingrange of the hand-lever 55 of about 90 the longitudinal slide istravelling only a fraction of the total length of its shifting range. Inorder to control the total shifting range of the slide theconnecting-rod isfor connecting the leverarm 58-provided with several,for instance three mortise holes 61 for the connecting pin of lever 58.In the present embodiment of the invention the mortise holes 61 of theconnecting-rod 59 are connected with each other by longitudinal slots 62(see Fig. 4). The mortise pin of lever arm 58 is made up, as shown inFig. 5, by a socket 63 in which a pin 64 is inserted fitting into theslots 62 of connecting rod 59, and it is held against the lower side ofthe connecting-rod 59 by a spring 65 with a lower stop-dog 66. Whenhand-lever 55 or, respectively, its short lever-arm 58 is to be changedover to another mortise hole 61, it is slightly raised whereby itsjournal 56 moves upwards in its bearing. At the same time the socket 63forming the mortise pin is disengaged from the connecting-rod 59, whilstpin 64 places itself with head 66 on the lower side of connecting-rod59, that is to say it remains engaged with the connecting-rod. Now thehand-lever 55 can be pivoted laterally in raised position, whereby pin64 slides into one of the longitudinal slots 62. During this lateralswing-out movement socket 63 forming the mortise pin will then by itselffall into the next mortise hole 61 when the force directed upwards is nolonger exercised on the hand-lever. I

The longitudinal slide 52 serves the purpose of clamping the workpiece.Its front may be equipped with a supporting rib 68 for the workpiece. Ascrew 69 is provided for keeping the supporting rib 68 in position,which screw extends through a vertical slot 70 of the supporting rib andis screwed onto the body 52 of the slide. In order to preventover-swinging the supporting rib 68 is guided in a groove 71 of the bodyof the slide. After loosening screw 69 the supporting rib may beadjusted upward or downward to correspond with the size of theworkpiece. Moreover, it may be removed entirely by completelyu-nscrewing the screw. The workpiece is pressed against the frontsurface of longitudinal slide 52 in the usual manner by a clamp 72, andis thereby held fast. In order to fix the clamp holder 73, the lower endof slide 52 is provided with bore-hole 74 in which pin 75 of holder 73may be fixed by means of set screw 76.

For adjusting the workpiece to the mortise chain 7 the following methodsmay be followed:

The longitudinal slide 52 can be shifted in the longitudinal directionalong the cross slide 40 by moving the hand lever 55, and by turning thehand wheel 43 in transverse direction together with the cross slide. Bythe longitudinal shifting of the slide 52 with the workpiece clampedthereon, the slot produced in the workpiece, by the mortising chainafter themotor has been moved downwardly canbe'widened. .The position ofthe slot in transverse direction of the workpiece may be adjusted byshifting the cross slide. If key seats are to be cut, the longitudinalslide 52 is correspondingly adjusted in vertical plane. Asdescribedabove, this can be made by disengaging the holding pin 45 andturning the cross slide 40 round the axis of'its guide pin 41, and thenlock.- ing the holding pin 45 in a corresponding tooth space of thetooth segment 46 on part 33 to the desired inclination. If oblique slotsare to'be cut, the longitudinal slide 52 must have a correspondingshifting position in horizontal plane. For this purpose, the [part 33 isturned around the vertical axis of its pivot 35. Thus the longitudinalslide 52 together with the workpiece can be adjusted in position withregard to the mortising in order to precisely adapt the clamping surfaceof its workpiece to the run of the mortise chain. With theround-barguidance 5353 provided here this readjustment can be achieved in a verysimple manner.

According to Figs. 6 and 7 the lower round bar 53 passes through bores54 of the front walls 54 of the longitudinal slide 52. The bores 54'have a larger di ameter than the round bar 53 which is journalled inlugs 79 with end journals 78 the diameter of which is smaller than thatof the round bar 53. The lugs 79 are adjustably fixed on the outside offront-Walls 54 by means of a fastening screw 81 passing through a slot80 transversely to the longitudinal direction of the slide. This makespossible, by swinging the longitudinal slide 52 around the upper roundbar 53, to set the longitudinal slide 52 in an oblique position by smalldegrees to the lower round bar. In order to achieve this it is simplyrequired to loosen the fixing screws 81 of the lugs 79, to

swing .out the slide from the lower round bar, and to.

tighten the screws again in the new position. For precise adjustment ofthe oblique position of the slide, setscrews 82 are provided in thefront-walls 54 of the longitudinal slide, which set-screws areadjustable against the lower round bar 53.

In Figs. 8 and 9 another embodiment is shown of the device forreadjusting the longitudinal slide 52 to the lower round bar 53. Heretoo the lower round bar has a margin all around for its movement inlarge bore holes in the side walls 54.- Lugs 84 rotatably mounted onpins 83 are provided on the outside of the front-walls 54 in which lugsthe lower round bar 53 is journalled with eccentrically arranged lightend-journals 85. On one frontside of the table the eccentric journal 85projects through lug84 and has a hand-lever 86 on its free end. Turningthe lower round bar 53 by means of this hand-lever,-

the lower end of the slide 52 is moved transversely to the lowerguide-rod 53 in consequence of the eccentric arrangement of the pin 83.The extent of the transverse adjustment may incase of need be read off ascale acting in conjunction with the hand-lever 86.

On both sides of the mortise chain 7 sliding rods 88 and 89 are providedin the manner known hitherto, one

of which rods (89) has a chip breaker 90 at its lower end, while theother one is provided with a sliding foot 91. Both these sliding rodsare, in the embodiment Figs. 1 and 2, guided in a protective casing 93on the front, swinging around a vertical axle on motor cage 5. Thedownward movement of the sliding rods is limited by set collars 94, 95which serve at the same time as deadweights and are adjustably fixed atthe upper ends of the sliding rods projecting from casing 93. Whenlowering the mortise chain driving motor, at first the chip breaker 90of the sliding rod 89, and following it the sliding shoe 91 of rod 88,superimpose themselves on the workpiece on both sides of the mortisingchain penetrating the workpiece. In the embodiment according to Fig. 10the sliding bars 88 and 89 are made as rectangular bars and are thussafe against turning. Their sliding guidance is formed by grooves 96open on one side, arranged on the inside of the protective casing 93,and passing through the wholelength. The sliding rods are securedagainst falling out of the grooves 96 by pins 97 which at least at twopoints extend across the grooves.

The operation of the machine is as follows:

,When the hand lever 15 is first swung away laterally from the catch pin20 and then downwardly, also the motor 5 with the mortising chain 7ismoved downwards and simultaneously the spring 14 is tensioned. Asdescribed above, the switch lever 22 of the motor switch is turned sothat the motor will be switched on after a short downward stroke beforethe mortising chain has reached the workpiece clamped on thelongitudinal slide 52. During the further downward movement of the motorthe mortising chain penetrates into the workpiece producinga slot whichmay, as described above, be extended by lateral shifting of thelongitudinal slide 52 by means of the hand lever 55, or which, dependingon the adjusting position of the slide, may be a key seat or an obliqueslot. The downward movement of the motor which determines the depth ofthe slot is limited by the stop pin 31 at the lower end collar or stopring 28. After;

the slot is cut, the handlevcr is released, whereupon the spring 14brings the motor automatically back into its upper end position and themortising chain out of theworkpicce. During the last portion of thereturn stroke the switch lever 22 is turned and the motor automaticallyswitched off. If it is desired not to switch off the motor, the stopring 29 is brought into its effective position where it limits theupward movement of the motor before the motor is switched off.

We claim as our invention:

1. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool and tool mount unit connected to the motorand extending downwardly therefrom, a guide element rotatably adjustablearound a vertical axis on the lower side of the frame to extendvertically therefrom, a cross slide mounted on the guide element to beadjustable in a horizontal plane, a stationary guide pin for the crossslide to adjustably support the latter in a horizontaldirection, aspindle in threaded engagement with the guide pin and having means torotate the spindle, the cross slide being rotatable with the guide pinlimited in its movement by the guide element, and means mounted on thecross slide and the guide element to lock the cross slide in adjustedposition.

2. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool andtool mount unit connected to the motor andextending downwardly therefrom, a guide element rotatably adjustablearound a vertical axis on the lower side of the frame to extendvertically therefrom, a cross slide mounted on the guide element to beadjustable in a horizontal plane, a longitudinal slide mounted forsliding movement on the cross slide and adapted to receive and clamp thework to be mortised, a hand lever connected to the longitudinal slide tomove the latter on the cross slide, and a connecting rod connected tothe longitudinal slide at one end and the other end to a short lever armof the hand lever.

3. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool and tool mount unit connected to the motorand extending downwardly therefrom, a guide element rotatably adjustablearound a vertical axis on the lower side of the frame to extend,vertically therefrom, a cross slide mounted on the guide element to beadjustable in a horizontal plane, a longitudinal slide mounted forsliding movement on the cross slide and adapted to receive and clamp thework to be mortised, a hand lever connected tothe longitudinal slide tomove the latter on the cross slide, and a connecting rod connected tothe longitudinal slide at one end andthe other end to a short lever armof the hand lever, the short lever arm having a plurality of points forconnection of the short lever arm to the connecting rod. 1

4. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon,

a tool and tool mount unit connected to the motor and extendingdownwardly therefrom, a guide element rotatably adjustable around avertical axis on the lower side of the frame to extend verticallytherefrom, a cross slide mounted on the guide element to be adjustablein a horizontal plane, a longitudinal slide mounted for sliding movementon the cross slide and adapted to receive and clamp the .work to bemortised, and a plurality of circular bars provided one over the otherfor the longitudinal slide whereby the bars provide the means to guidethe longitudinal slide on the cross slide, the longitudinal slide beingswingable about the lower circular bar to adjust the path of movement ofthe mortising tool.

5. A chain mortising machine comprising a frame adapted, to be securedto a vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool and tool mount unit connected to the motorand extending downwardly therefrom, a guide element rotat ablyadjustable around a vertical axis on the lower side of the frame toextend vertically therefrom, a cross slide mounted on the guide elementto be adjustable in a horizontal plane, a longitudinal slide mounted forsliding movement on the cross slide and adapted to receive and clamp thework to be mortised, a plurality of circular bars provided one over theother for the longitudinal slide whereby the bars provide the means toguide the longitudinal slide on the cross slide, the longitudinal slidebeing swingable about the lower circular bar to adjust the path ofmovement of the mortising tool, and lugs provided secured to thelongitudinal slide whereby the lower circular bar is adjustably mountedrelative to the longitudinal slide.

6. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool and tool mount unit connected to the motorand extending downwardly therefrom, a guide element rotatably adjustablearound a vertical axis on the lower side of the frame to extendvertically therefrom, a cross slide mounted on the guide element to beadjustable in a horizontal plane, a longitudinal slide mounted forsliding movement on the cross slide and adapted to receive and clamp thework to be mortised, the longitudinal slide having walls extendingbackwards therefrom, and rodlike stops provided in said walls to limitthe longitudinal movement of the slide by means of projections on thecross slide.

7. A chain mortising machine comprising a frame adapted to be secured toa vertical support, a motor mounted on said frame for verticaladjustment thereon, a tool and tool mount unit connected to the motorand extending downwardly therefrom, a guide element rotatably adjustablearound a vertical axis on the lower side of the frame to extendvertically therefrom, a cross slide mounted on the guide element to beadjustable in a horizontal plane, a longitudinal slide mounted forsliding movement on the cross slide and adapted to receive and clamp thework to be mortised, a plurality of circular bars supported on the frameand on which the motor is slidably mounted, and a lever arm'pivotallymounted on the frameand connected to adjust the motor, a catch pin beingmounted on the frame to hold the lever in the upper raised position ofthe motor.

References Cited in the file of this patent UNITED STATES PATENTS495,350 Loetscher Apr. 11, 1893 7 642,073 Brown Jan. 30, 1900 646,125Meserve Mar. 27, 1900 673,378 Brown May 7, 1901 1,620,895 r Kandera Mar.15, 1927 1,892,246 Mohns- Dec. 27, 1932 2,645,255 Francescatti et al.July 14, 1953 FOREIGN PATENTS 3,537/26 Australia Aug. 30, 1926

